Surface passivation with organic ammoniums improves perovskite solar cell performance by forming 2D/quasi-2D structures or adsorbing onto surfaces.However,complexity from mixed phases can trigger phase transitions,com...Surface passivation with organic ammoniums improves perovskite solar cell performance by forming 2D/quasi-2D structures or adsorbing onto surfaces.However,complexity from mixed phases can trigger phase transitions,compromising stability.The control of surface dimensionality after organic ammonium passivation presents significant importance to device stability.In this study,we developed a poly-fluorination strategy for surface treatment in perovskite solar cells,which enabled a high and durable interfacial phase purity after surface passivation.The locked surface dimensionality of perovskite was achieved through robust interaction between the poly-fluorinated ammoniums and the perovskite surface,along with the steric hindrance imparted by fluorine atoms,reducing its reactivity and penetration capabilities.The high hydrophobicity of the poly-fluorinated surface also aids in moisture resistance of the perovskite layer.The champion device achieved a power conversion efficiency(PCE)of 25.2% with certified 24.6%,with 90% of its initial PCE retained after approximately 1200 h under continuous 1-sun illumination,and over 14,400 h storage stability and superior stability under high-temperature operation.展开更多
基金grants(grant numbers LR24F040001,LD24E020001 and LD22E020002)from the Natural Science Foundation of Zhejiang Province of Chinathe National Natural Science Foundation of China(grant number 62274146)+1 种基金the support of Key R&D Program of Zhejiang(2024SSYS0061)supported by the Fundamental Research Funds for the Central Universities(226-2022-00200).
文摘Surface passivation with organic ammoniums improves perovskite solar cell performance by forming 2D/quasi-2D structures or adsorbing onto surfaces.However,complexity from mixed phases can trigger phase transitions,compromising stability.The control of surface dimensionality after organic ammonium passivation presents significant importance to device stability.In this study,we developed a poly-fluorination strategy for surface treatment in perovskite solar cells,which enabled a high and durable interfacial phase purity after surface passivation.The locked surface dimensionality of perovskite was achieved through robust interaction between the poly-fluorinated ammoniums and the perovskite surface,along with the steric hindrance imparted by fluorine atoms,reducing its reactivity and penetration capabilities.The high hydrophobicity of the poly-fluorinated surface also aids in moisture resistance of the perovskite layer.The champion device achieved a power conversion efficiency(PCE)of 25.2% with certified 24.6%,with 90% of its initial PCE retained after approximately 1200 h under continuous 1-sun illumination,and over 14,400 h storage stability and superior stability under high-temperature operation.